Cast-aluminum stack chair

ABSTRACT

A chair capable of being stacked for storage and releasably coupled or ganged in side-by-side relation forming a row of like chairs each having a seat assembly mounted in a cantilever fashion to a base assembly. The base assembly includes a pair of substantially identical leg units; one leg unit provides the two front legs of the chair and the other unit provides the two rear legs of the chair. The legs of each pair are joined at their upper ends to an intermediate horizontal crossmember thereby forming the leg unit; the crossmembers of the two leg units are secured in back-to-back relation so as to form the base assembly. Mating slots are provided in the abutted crossmembers so as to form a mortise joint when the base is assembled. The seat assembly includes two identical L-shaped frame members between which are disposed and to which are secured a backrest and seat. The seat assembly is mounted to the base assembly by means of a tongue or tenon adapted to fit into the mortise joint and which depends from a horizontally oriented section of each L-shaped frame member. The chair is assembled by inserting the tenons of the seat assembly into the mortises provided in the base assembly. A hole can be drilled through the crossmembers and the mortise and tenon joint so that appropriate mechanical fasteners can be inserted for firmly securing the seat assembly to the base assembly. The facing or opposed surfaces of the front and rear legs of each chair have stacking bosses provided thereon each having a horizontally oriented bottom surface. A plastic insert is installed on each leg to cover said bottom surface. Upon stacking of a pair of chairs, the plastic insert of the upper chair will engage upon the shoulder of the lower chair to prevent a metal-to-metal contact between the chairs which could mar or scratch the chairs&#39;&#39; finishes. A plurality of chairs may be coupled in side-by-side relation by providing a slot in the under portion of the shoulder of one chair in which can be engaged a crosshead of a connector member which projects outwardly from the side of an adjacent chair.

United States Patent [72] Inventor Jerome CarmelCaruso ArlingtonHeights, Ill. [21] Appl. No. 865,449 [22] Filed Oct. 10,1969 [45]Patented Oct. 5, 1971 [73] Assignee Shelby Williams Industries, Inc.Chicago, Ill.

[54] CAST-ALUMINUM STACK CHAIR 22 Claims, 11 Drawing Figs.

[52] U.S.Cl 297/239, 297/248, 297/445 [51] Int. Cl A47c3/04 [50] Fieldof Search 297/239, 248, 249, 160,457,440, 162, 445

[56] References Cited UNITED STATES PATENTS 2,747,654 5/1956 Chapman297/445 X 3,031,227 4/l962 Van Buren 297/239 3,123,399 3/1964 Wilson297/239 3,159,425 12/1964 Engstrom. 297/239 3,203,731 8/1965 Krueger....297/248 3,3I9,999 5/1967 Liberman. 297/239 3,328,075 6/1967 Albinson297/239 3,431,022 3/1969 Poppe 297/445 3,497,262 2/1970 Piretti 297/239FOREIGN PATENTS 528,654 8/1956 Canada 297/445 Primary Examiner-FrancisK, Zugel Attorney-Silverman & Cass ABSTRACT: A chair capable of beingstacked for storage and releasably coupled or ganged in side-by-siderelation forming a row of like chairs each having a seat assemblymounted in a cantilever fashion to a base assembly. The base assemblyincludes a pair of substantially identical leg units; one leg unitprovides the two front legs of the chair and the other unit provides thetwo rear legs of the chair. The legs of each pair are joined at theirupper ends to an intermediate horizontal crossmember thereby forming theleg unit; the crossmembers of the two leg units are secured inback-to-back relation so as to form the base assembly. Mating slots areprovided in the abutted crossmembers so as to form a mortise joint whenthe base is assembled. The seat assembly includes two identical L-shaped frame members between which are disposed and to which are secureda backrest and seat. The seat assembly is mounted to the base assemblyby means of a tongue or tenon adapted to fit into the mortise joint andwhich depends from a horizontally oriented section of each L-shapedframe member. The chair is assembled by inserting the tenons of the seatassembly into the mortises provided in the base assembly. A hole can bedrilled through the crossmembers and the mortise and tenon joint so thatappropriate mechanical fasteners can be inserted for firmly securing theseat assembly to the base assemblyv The facing or opposed surfaces ofthe front and rear legs of each chair have stacking bosses providedthereon each having a horizontally oriented bottom surface. A plasticinsert is installed on each leg to cover said bottom surface. Uponstacking of a pair of chairs, the plastic insert of the upper chair willengage upon the shoulder of the lower chair to prevent a metal-to-metalcontact between the chairs which could mar or scratch the chairsfinishes, A plurality of chairs may be coupled in side-by-side relationby providing a slot in the under portion of the shoulder ofone chair inwhich can be engaged a crosshead of a connector member which projectsoutwardly from the side of an adjacent chair.

PATENTED EDT 5 l9?! SHEET 1 OF 3 PATENTEDUCT 5m! SHEET 2 OF 3 INVJN roeBACKGROUND OF THE INVENTION This invention relates to seating furnitureand more particu- A simple slip-lock construction is provided forcoupling one chair in side-by-side relation to another. An I-shapedcrosshead in the horizontal position is secured at one end to the baseassembly of one chair in such a manner that it prolarly, to aconstruction for a chair capable of being stacked for jects outwardlyfrom the side thereof- The adjacent chair can storage and coupled organged together in side-by-side relationship when in use.

Folding chairs have provided additional seating furniture for use inlarge halls such as auditoriums, synagogues, churches, and schools wheretemporary additional seating capacity is necessary. The problemspresented by these chairs, such as storage, weight and comfort have beenovercome by the use of nonfolding, rigid chairs capable of being stackedone upon another. Several United States patents have been issued whichteach different structures for stackable chairs.

One type of chair, formed with a unitary molded seat and backrestmounted to a tubular-metal leg assembly, is disclosed in US. Pat. Nos.2,952,300; 3,018,131; 3,025,105 and 3,084,977. These chairs have sidecross braces to provide rigidity and stacking and coupling means.However, these chairs do not provide the clean functional styling nowdemanded; nor are they capable of being fabricated from a reduced numberof parts and easily assembled.

Other chair constructions are known, but these disclose complex legassemblies such as represented in U.S. Pats. Nos. 2,588,417 and3,328,075 or stacking chairs with foldable back as represented in US.Pat. No. 3,203,721. These chairs have a large number of parts, are of arelatively complex construction and are not readily assembled.

Further, a stack chair having arms or alternatively, an integral writingtable is disclosed in US. Pat. No. Re. 25,985. However, this chaircannot be ganged to form a row of chairs, and moreover, it has a largenumber of parts.

Therefore, a chair, which can be stacked and coupled, has few parts, iseasily assembled, has clean functional lines and is light and strong,has, to the best of my knowledge, yet to be provided. Furthermore,without changing the basic structure, the chair should be capable ofbeing constructedwith or without arms and with or without a writingtable and still retain the desirable features enumerated above. Lastly,the chair must be capable of economic mass production. Preferably, thechair also should be capable of shipment in knockdown condition and beeasily assembled at the contemplated cite of use.

SUMMARY OF THE INVENTION The chair embodying the invention isconstructed from an easily fabricated base assembly and seat assembly.The base assembly has two identical leg units; each leg unit includestwo legs, either both front or both rear, and an intermediate horizontalcrossmember joined to the legs at their upper ends or shoulders. Whenthe two leg units are secured at the crossmembers in back-to-backrelation, four legs are provided for the chair, and the crossmembersprovide a support structure to which the seat assembly may be mounted.The seat assembly is fabricated from two identical L-shaped framesbetween which is disposed and secured backrest and seat members. Thechair is formed by mounting the seat assembly to the base assemblycrossmembers. The width or lateral dimension of the seat assembly may beless than the width of the base assembly so that the chairs may bestacked one upon another.

In a preferred embodiment, the seat assembly is secured to the baseassembly by means of a mortise and tenon arrangement. The mortise isprovided in the crossmembers, and mating depending tenons are providedon horizontally oriented sections of the L-shaped frame members. Thefastening means which secure one leg unit to the other can function tosupplement the mortise and tenon joint. Thus, in the preferredembodiment, a locking bolt can be extended through the cross memberthrough the mortise and tenon and fastened to the other crossmember.

be coupled by raising it slightly, aligning a slot provided in the underportion of the shoulder and end of the crosshead and lowering the chairso that the slot engages the crosshead end. Vertical support members canbe secured to the base assembly so as to provide armrests or writingtables. Chairs constructed with sidearms and writing table attachmentscan be stacked and ganged as hereinafter described.

The invention provides a chair having a small number of parts which canbe fabricated by mass production techniques. Furthermore, there are nocross braces between the front and rear legs or between the front legsor rear legs themselves, thereby providing a base assembly withuncluttered or clean, functional modern lines. The cost of the chair issignificantly reduced since there are few parts and many of the partsare duplicates of one another; moreover, the chair can be assembled in avery short length .of time by means of very simple fastening devices.This enables shipment in knockdown condition for the chair withattendant advantages. Due to the construction of the chair, many of theassemblies can be fabricated from lightweight materials, such asdie-cast aluminum. Therefore, the chair of this invention alleviatesmany of the problems heretofore prevalent in the art.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of achair embodying this invention;

FIG. 2 is an exploded perspective view depicting the elements of thechair of FIG. I with the backrest and seat not shown;

FIG. 3 is a side elevational view showing several chairs embodying theinvention in stacked or stored condition;

FIG,4 is a front elevational view showing three chairs coupled togetherin side-by-side relation;

FIG. 5 is a fragmentary sectional view taken along line 5-5 of FIG. 4and showing the crosshead in place in the ganging slots;

FIG. 6 is a fragmentary sectional view taken along line 6-6 of FIG. 4and showing the tapered end of the crosshead secured in place in aganging slot;

FIG. 7 is a fragmentary sectional view showing the straightsided end ofa crosshead poised for engagement with a ganging slot;

FIG. 8 is a fragmentary sectional view taken along line 8-8 of FIG. 1and showing a locking bolt extended through the crossmembers and mortiseand tenon joint;

FIG. 9 is a perspective view of a side support member which is adaptedto be secured to the base assembly;

FIG. 10 is a sectional view taken along line l0-- 10 of FIG. 9 and inthegeneral direction indicated showing the mounting head and gangingslot; and

FIG. 11 is a front elevational view showing several chairs stacked andwith writing table attachments oriented in the vertical position.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,reference numeral 10 designates generally a chair constructed inaccordance with this invention. A separate seat assembly, designatedgenerally by reference numeral 12, is secured to a base assembly.designated generally 14.

The seat assembly 12 includes a pair of identical, L-shaped framemembers 16 between which are mounted a backrest 18 and seat 20. The baseassembly 14 includes two identical leg units 22, each of which includesa pair of front or rear legs 24 having shoulder portions 25 to which theends of an intermediate horizontal crossmember 26 are joined. Both legunits 22 are fastened together along the inner faces 28 of thecrossmembers so as to form the base assembly 14. In order to provide astable base, the legs 24 slope downwardly and away from the inner face28 so that the front and rear legs are divergent. Suitable fasteningmeans are used to secure together the two leg units in back-to-backrelation.

A preferred method for so securing said leg units 22 together is toprovide internally threaded holes 30 in the crossmembers into whichlocking bolts 32 can be threadedly engaged. Nut and bolt arrangements,clip arrangements, or even tongue and groove arrangements may be usedinstead of the preferred locking means described and illustrated.

The crossmember 26 can be straight or curved as shown in FIG. 2. Thecurvature of the member 26 illustrated in FIG. 2 serves to accommodate acurved seat assembly which is especially comfortable.

The seat assembly 12 can be secured to the base assembly 14 in numerousways. However, a mortise and tenon joint is preferred since it providesthe greatest ease of the fabrication, the fewest number of parts,easiest assembly, and the desired stability. The mortise is formed byproviding a pair of slots 34 in each crossmember 26. The slots in theopposing crossmembers can be brought into registry when the leg units 22are joined together to form the base assembly 14, giving rise to amortise or generally rectangular cavity. In the preferred embodiment,two such mortises are provided. A heavier section may be provided in theportion of the crossmember in which the slots 34 are formed.

Each L-shaped frame member 16 is provided with an integral dependingtenon 36 along its horizontal section or part. The position of the tenon36 along the horizontal part is determined by the size of the seat andexpected location of the center of gravity of the user. The size andshape of the tenon is such that it can be matingly engaged in themortise. Normally, the seat assembly and base assembly are constructedseparately and the tenons are then inserted into the mortises so as tomount the seat assembly to the base assembly. An alternative procedurewould be to make the mortise slightly smaller than the tenon, so as torequire the larger tenon to be force fitted into the smaller mortise.

Referring to FIG. 2, open-ended holes 35 are provided which extendthrough the tenon 36. When the mortise and tenon are matingly engaged,the holes 30 and 35 in the crossmember and tenon are aligned. A lockingbolt 32 is threaded into the aligned holes in the crossmembers and tenonfor locking the pieces together. The bolt may then be secured by a nutor by a threaded internal connection. Thus, the base assembly can beerected and the seat assembly mounted thereto in a single, simpleoperation.

In order to stack chair 10, the outer edges of the seat assembly 12 mustbe displaced inwardly of the outer sides of the base assembly 14. Thisinward displacement of the seat assembly allows the legs of a secondchair to fit over the first chair for stacking. The chairs can bestacked also by setting one on top of another in which case thecrossmember of one chair would rest on the seat or against the L-shapedframes of a lower chair. However, such an arrangement is undesirablesince the chairs and seat could be scratched, marked or otherwisedisfigured. To prevent such possible disfiguration of the chairs,Stacking bosses 38 are provided along the opposed faces of the front andrear legs, that is, the front faces of the rear legs and rear faces ofthe front legs. The bosses have a generally horizontal bottom surfaceover which a plastic insert is installed so that when a chair isstacked, the plastic insert rests on the top surface of the leg shouldertherebelow thus providing nondamaging plastic-to-metal contact. The bossis positioned along the length of the leg at a point such that a spacewill be provided between the seat of lower chair and crossmember of theupper chair. Furthermore, the bosses maintain each chair in a fixedhorizontal position so as to reduce the tipping tendency of the stack ofchairs.

The chairs 10 are shown stacked in FIG. 3. Chairs 10a through 10d arestacked one upon another and it is seen that the stacking bosses 38arest upon the top surface or shoulder of the legs 24b of the next lowerchair 10b. From this view it can be seen that the only contact betweenchairs is at the stacking boss and leg shoulder, thus avoidingdisfiguring of the chairs when they are stacked.

A plurality of ganged or coupled chairs in side-by-side relation isshown in FIG. 4. Such coupling allows the chairs to be temporarilyarranged in fixed rows for the seating of large audiences. By virtue ofthe construction of these chairs, a very simple ganging device isprovided. This device can be characterized as an I-shaped crosshead 40.The leg shoulders 25 are slotted along the inner faces 28 and the undersurface of the shoulder. Thus, when two leg assemblies are broughttogether, the slots 42 are in registry and provide a cavity in which oneend of the 1" may be received. Thus, when one chair, having thecrosshead in position, is brought in side-by-side relation to a second,the projecting end of the I" may be inserted into the ganging slot 42 inthe base assembly of the second chair. The crosshead 40 may beconstructed of a resilient material such as plastic and the slots 42 mayhave appropriate detents or projections therein so as to releasablysecure the crosshead in place. Thus, crosshead can be inserted into theslot after the base assembly has been constructed.

If it is desired to fixedly secure the crosshead 40 to the chair, theganging slots are provided with reentrant angles and one end of the I"is tapered in conformity with the slots. Thus, once the chair has beenassembled and the crosshead is secured in place at its tapered end, itcannot be removed. A slot having a reentrant angle with the tapered endof the crosshead 40 disposed therein is depicted in cross section inFIG. 6. From the view it can be appreciated that the crosshead is firmlysecured in place and cannot be removed except by dissembling the chair.The untapered end of the crosshead releasably engages a ganging slot inan adjacent chair. As is apparent form FIG. 7, the untapered end can befitted into the ganging slot through the opening in the bottom andremoved in a similar fashion. FIG. 5 shows the crosshead in place in twoadjacent ganging slots. From that view, the connection between adjacentchairs by means of the crosshead is readily apparent.

One of the great advantages of the chair disclosed herein is that it isconstructed of few parts, many of which are identical. For example, theleg units are identical members, either of which can be the front orrear leg unit. Thus, the base structure is formed from two members whichare essentially identical and need not be oriented in their manufacture.The frame members for the seat assembly are identical and, similarly, donot require orientation when fabricated. Furthermore, the seat assemblymay be secured to the base assembly by means of only two bolts. Thestructural member elements used in making the chair 10 of the inventionmay be die cast thereby eliminating multiple manufacturing andassembling procedures with attendant material and significant costsavings.

Using the basic construction as described above, the chair 10 can bemodified to accommodate armrests and/or writing table attachmentsintegral therewith. The vertical support member 50, shown in FIG. 9, canbe used to support either the armrest or table. The upper end of thesupport 50 has protruding horizontally oriented flanges 52 on which thearmrest or table member is secured. The member 50 is secured at itslower end to the base assembly 14 by an integral inwardly projectingconnecting head 54, similar to the crosshead 40. The head 54 has atapered end which can be fixed in position in the reentrant gangingslots 42. Thus, the support member 50 is secured to the base assembly inthe same manner as the tapered end of crosshead 40; by virtue of thisconnection the flange member is located outboard of the leg assembly soas not to interfere with the stacking of the chairs. The outboard sideof the lower end of the support 50 is provided with a downwardly openingslot 56 which may be used to engage an end of the crosshead 40 forganging. If one armrest is secured to the same side of a plurality ofchairs, they can be stacked and ganged as previously described. However,if two armrests are used with each chair, they may be stacked but notganged, because ganging slots in which the tapered end of the crosshead40 can be fixedly secured are not provided due to dimensionedlimitations.

A chair having a writing table member on one side normally is notprovided with an armrest on its opposite side. Thus, the chair can beganged in the fashion described for a chair having one armrest. In orderto stack such a chair, the table member is pivotally secured to theupper flanges 52 so that it may be rotated about a horizontal axisupwardly and outwardly from the chair, thereby vertically orienting itoutboard of the support member. The stacking of such chairs is depictedin FIG. 11. Releasable locking mechanisms can be provided to lock thewriting table member in its vertical position for stacking and in itshorizontal position for writing or use.

What is desired to be secured by Letters Patent of the United States is:I

l. A chair frame assembly comprising, a base frame and a seat frame;

a. said base frame comprising a pair of similar integral leg units eachof which comprises;

i. a pair of legs joined to a crossmember at shoulder for mations at theupper ends of said legs;

ii. the crossmember having an inner face from which said legs are canteddownwardly and in a direction away from the inner face;

iii. the leg units being arranged in back-to-back relation alongabutting inner faces of the crossmembers;

b. the seat frame comprising a pair of similar L-shaped integral framemembers adapted to mount i. a seat between horizontally orientedsections of the frame members and ii. a backrest between verticallyoriented sections of the frame members; and

c. means for mounting the seat frame to the base frame, said meansincluding said crossmembers having at least a pair of upwardly openingmortises on opposite sides of said opposed inner faces thereof and saidseat frame members each having an integral depending tenon matinglyengageable in a said mortise for holding same upright on the base framein position to mount said seat and backrest.

2. The assembly as recited in claim 1 in which said leg units andL-shaped frame members respectively are integral, castmetal members.

3. The assembly as recited in claim 1 wherein the leg units areassembled together by mechanical fasteners engaged with thecrossmembers.

4. The assembly as recited in claim 1 wherein the cross members areconcave in cross section and the seat is of conforming configuration formounting thereon in a cantilevertype support position.

5. The assembly as recited in claim 4 wherein the width of the frameassembly is less than the width of the base frame.

6. The assembly as recited in claim 1 wherein the width of the seat isless than that of the base and the seat frame is mounted to the baseframe inside the shoulder formations with said formations exposed.

7. The assembly as recited in claim 1 wherein the leg unit is a unitarypiece.

8. The assembly as recited in claim 1 wherein the L-shaped frame memberis a unitary piece.

9. The assembly as recited in claim 1 wherein the base frame has a pairof ganging slots provided in the underside of the shoulder formations,and l-shaped crosshead connector members are engaged in said gangingslots.

10. The assembly as recited in claim 9 wherein said connector membersare resiliently and releasably engaged in the ganging slots.

11. The assembly as recited in claim 1 having at least one verticalsupport member secured to the base frame at a side thereof.

12. The assembly as recited in claim 1 wherein at least one armrest issecured to said vertical support.

13. The assembly as recited in claim 1 wherein a writing tableattachment is mounted to the support member.

14. The assembly as claimed in claim 1 in which said mounting meansinclude means to hold said crossmembers together with the tenons engagedin said mortises.

15. The assembly as claimed in claim 14 in which said lastnamed meanscooperate with said tenons and mortises for holding said inner facestogether in said abutting relationship.

16. The assembly as recited in claim 5 wherein a plurality of stackingbosses is provided, one boss projecting from each leg toward the opposedleg and each boss having a horizontal surface for stacking contact.

17. The assembly as recited in claim 16 wherein the stacking bosses arearranged to contact the upper surfaces of the leg shoulder formation ofa lower assembly upon which said assembly is stacked such that when theassemblies are stacked, a space is provided between the seat and seatframe member of the lower assembly and the lower surface of thecrossmember of the upper assembly.

18. A chair comprising, a base assembly and a seat assembly;

a. said base assembly including a pair of similar leg units each ofwhich comprises;

i. a pair of legs joined to a crossmember at shoulder formation at theupper ends of said legs;

ii. the crossmember having an inner face from which said legs are canteddownwardly and in a direction away from the inner face;

iii. the leg units being secured in back-to-back relation along opposedinner faces of the crossmembers;

iv. said crossmembers having mortise means;

b. the seat assembly having a pair of similar L-shaped frame membersincluding,

i. a seat mounted between horizontally oriented sections of the framemembers and ii. a backrest mounted between vertically oriented sectionsof the frame members;

iii. depending tenon means matingly engaged in said mortise means forsupporting the seat assembly upright on the base assembly; and V c. theseat assembly beingsecured to the base assembly by means of a fastenerpassing through each said crossmember and tenon means.

l9. A chair comprising, a base assembly and a seat assembly;

a. said base assembly including a pair of similar leg units each ofwhich comprises;

i. a pair of legs joined to a crossmember at shoulder formations at theupper ends of said legs;

ii. the crossmember having an inner face from which said legs are canteddownwardly and in a direction away from the inner face;

iii. the leg units being secured in back-to-back relation along opposedinner faces of the crossmembers;

b. the seat assembly having a pair of similar L-shaped frame members andincluding,

i. a seat mounted between horizontally oriented sections of the framemembers and ii. a backrest mounted between vertically oriented sectionsof the frame members;

c. means for mounting the seat assembly to the base assembly; and

d. said base assembly having a pair of ganging slots provided in theunderside of the shoulder formations, each ganging slot being providedwith a reentrant angle, and l-shaped crosshead connector members engagedin said ganging slots.

20. The chair as recited in claim 19 wherein one end of the crosshead istapered and shaped to matingly engage the ganging slot and be securedtherein and the other end is untapered and of a size to slidably engagethe ganging slot.

21. A chair comprising, a base assembly and a seat assembly;

a. said base assembly including a pair of similar leg units each ofwhich comprises;

i. a pair of legs joined to a crossmember at shoulder formations at theupper ends of said legs;

ii. the crossmember having an inner face from which said legs are canteddownwardly and in a direction away from the inner face;

iii. the leg units being secured in back-to-back relation along opposedinner faces of the crossmembers;

b. the seat assembly having a pair of similar L-shaped frame members andincluding,

i. a seat mounted between horizontally oriented sections of the framemembers and ii. a backrest mounted between vertically oriented sectionsof the frame members; and

c. means for mounting the seat assembly to the base assembly.

d. the base assembly having at least one vertical support member securedthereto at a side thereof, said vertical support member having, at itslower end, an integral inwardly projecting connecting head, having an 1"shape and a downwardly tapered end flange, and said base assembly havingat least one ganging slot in the underside of the leg shoulderformation, said slot having a reentrant angle and adapted to engage thetapered end of the connecting head thereby securing the support memberoutboard of the base assembly.

22. The chair as recited in claim 21 wherein the support member has adownwardly opening ganging slot provided in its lower end.

P0405" UNITED STATES PATENT OFFICE 5 5 CERTIFICATE O CORRECTION PatentN6. 3,610,686 Dated October 5, 1971 Inventor(s) Jerome Carmel Caruso Itis certified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 5, line 54, before "frame" insert --seat--. Column 5, line 56,after "seat" insert --frame--. Column 5, line 56, after "base" insert--frame--. Column 6, lines 25 and 26, after "shoulder" change"formation" to --formations--.

igned and sealed this 9th day of May 1972.

(SEAL) fattest:

:GDHAHD ILFLEICIMR,JR. ROBERT GOTTSCHALK fxlltexsbj mg Office 1"Commissioner of Pa tents

1. A chair frame assembly comprising, a base frame and a seat frame; a.said base frame comprising a pair of similar integral leg units each ofwhich comprises; i. a pair of legs joined to a crossmember at shoulderformations at the upper ends of said legs; ii. the crossmember having aninner face from which said legs are canted downwardly and in a directionaway from the inner face; iii. the leg units being arranged inback-to-back relation along abutting inner faces of the crossmembers; b.the seat frame comprising a pair of similar L-shaped integral framemembers adapted to mount i. a seat between horizontally orientedsections of the frame members and ii. a backrest between verticallyoriented sections of the frame members; and c. means for mounting theseat frame to the base frame, said means including said crossmembershaving at least a pair of upwardly opening mortises on opposite sides ofsaid opposed inner faces thereof and said seat frame members each havingan integral depending tenon matingly engageable in a said mortise forholding same upright on the base frame in position to mount said seatand backrest.
 2. The assembly as recited in claim 1 in which said legunits and L-shaped frame members respectively are integral, cast-metalmembers.
 3. The assembly as recited in claim 1 wherein the leg units areassembled together by mechanical fasteners engaged with thecrossmembers.
 4. The assembly as recited in claim 1 wherein the crossmembers are concave in cross section and the seat is of conformingconfiguration for mounting thereon in a cantilever-type supportposition.
 5. The assembly as recited in claim 4 wherein the width of theframe assembly is less than the width of the base frame.
 6. The assemblyas recited in claim 1 wherein the width of the seat is less than that ofthe base and the seat frame is mounted to the base frame inside theshoulder formations with said formations exposed.
 7. The assembly asrecited in claim 1 wherein the leg unit is a unitary piece.
 8. Theassembly as recited in claim 1 wherein the L-shaped frame member is aunitary piece.
 9. The assembly as recited in claim 1 wherein the baseframe has a pair of ganging slots provided in the underside of theshoulder formations, and I-shaped crosshead connector members areengaged in said ganging slots.
 10. The assembly as recited in claim 9wherein said connector members are resiliently and releasably engaged inthe ganging slots.
 11. The assembly as recited in claim 1 having atleast one vertical support member secured to the base frame at a sidethereof.
 12. The assembly as recited in claim 1 wherein at least onearmrest is secured to said vertical support.
 13. The assembly as recitedin claim 1 wherein a writing table attachment is mounted to the supportmember.
 14. The assembly as claimed in claim 1 in which said mountingmeans include means to hold said crossmembers together with the tenonsengaged in said mortises.
 15. The assembly as claimed in claim 14 inwhich said last-named means cooperate with said tenons and mortises forholding said inner faces together in said abutting relationship.
 16. Theassembly as recited in claim 5 wherein a plurality of stacking bosses isprovided, one boss projecting from each leg toward the opposed leg andeach boss having a horizontal surface for stacking contact.
 17. Theassembly as recited in claim 16 wherein the stacking bosses are arrangedto contact the upper surfaces of the leg shoulder formation of a lowerassembly upon which said assembly is stacked such that when theassemblies are stacked, a space is provided between the seat and seatframe member of the lower assembly and the lower surface of thecRossmember of the upper assembly.
 18. A chair comprising, a baseassembly and a seat assembly; a. said base assembly including a pair ofsimilar leg units each of which comprises; i. a pair of legs joined to acrossmember at shoulder formation at the upper ends of said legs; ii.the crossmember having an inner face from which said legs are canteddownwardly and in a direction away from the inner face; iii. the legunits being secured in back-to-back relation along opposed inner facesof the crossmembers; iv. said crossmembers having mortise means; b. theseat assembly having a pair of similar L-shaped frame members including,i. a seat mounted between horizontally oriented sections of the framemembers and ii. a backrest mounted between vertically oriented sectionsof the frame members; iii. depending tenon means matingly engaged insaid mortise means for supporting the seat assembly upright on the baseassembly; and c. the seat assembly being secured to the base assembly bymeans of a fastener passing through each said crossmember and tenonmeans.
 19. A chair comprising, a base assembly and a seat assembly; a.said base assembly including a pair of similar leg units each of whichcomprises; i. a pair of legs joined to a crossmember at shoulderformations at the upper ends of said legs; ii. the crossmember having aninner face from which said legs are canted downwardly and in a directionaway from the inner face; iii. the leg units being secured inback-to-back relation along opposed inner faces of the crossmembers; b.the seat assembly having a pair of similar L-shaped frame members andincluding, i. a seat mounted between horizontally oriented sections ofthe frame members and ii. a backrest mounted between vertically orientedsections of the frame members; c. means for mounting the seat assemblyto the base assembly; and d. said base assembly having a pair of gangingslots provided in the underside of the shoulder formations, each gangingslot being provided with a reentrant angle, and I-shaped crossheadconnector members engaged in said ganging slots.
 20. The chair asrecited in claim 19 wherein one end of the crosshead is tapered andshaped to matingly engage the ganging slot and be secured therein andthe other end is untapered and of a size to slidably engage the gangingslot.
 21. A chair comprising, a base assembly and a seat assembly; a.said base assembly including a pair of similar leg units each of whichcomprises; i. a pair of legs joined to a crossmember at shoulderformations at the upper ends of said legs; ii. the crossmember having aninner face from which said legs are canted downwardly and in a directionaway from the inner face; iii. the leg units being secured inback-to-back relation along opposed inner faces of the crossmembers; b.the seat assembly having a pair of similar L-shaped frame members andincluding, i. a seat mounted between horizontally oriented sections ofthe frame members and ii. a backrest mounted between vertically orientedsections of the frame members; and c. means for mounting the seatassembly to the base assembly. d. the base assembly having at least onevertical support member secured thereto at a side thereof, said verticalsupport member having, at its lower end, an integral inwardly projectingconnecting head, having an ''''I'''' shape and a downwardly tapered endflange, and said base assembly having at least one ganging slot in theunderside of the leg shoulder formation, said slot having a reentrantangle and adapted to engage the tapered end of the connecting headthereby securing the support member outboard of the base assembly. 22.The chair as recited in claim 21 wherein the support member has adownwardly opening ganging slot provided in its lower end.